Murata Manufacturing Co., Ltd.

Masami Sugitani

Takashi Shikama

Hisato Oshima

Katsuyuki Uchida

Yukio Sakamoto

Junichi Inoue

Iwao Fukutani

Takahiro Yamamoto

Motoi Nishii

Kouichi Yamaguchi

Tatsuyuki Yamada

Toshio Kawabata

Satoshi Murata

Kaoru Tachibana

Takehiko Otsuki

Tetsuo Tanaka

Masaaki Kuboto

A composite inductor includes a block made of resin or rubber having a magnetic material dispersed therein. Spirally wound coils are buried in the block so that the coil axes of the coils are arranged in the same direction. The end portions of the coils are electrically connected to external electrodes provided on two surfaces of the block substantially at a right angle to the axes of the coils.

Composite inductor element

A bead inductor has excellent productivity and increased reliability in the connection between an internal conductor and external terminals. A method for manufacturing such a bead inductor includes the steps of forming an internal conductor and the external terminals as an integral, unitary member such that the external terminals are disposed at both ends of the internal conductor and electrically connected thereto; positioning the integral, unitary member in a metallic mold; and molding a resin material or a rubber material including a powdered magnetic substance in the metallic mold so as to embed the internal conductor therein.

Bead inductor and method of manufacturing same

A ceramic electronic component includes a ceramic sintered compact containing about 35 to 80 volume percent pores and an electrode provided inside the ceramic sintered compact. The pores are filled with resin or glass. This ceramic electronic component is formed by forming a green compact which includes an electrode therein with a ceramic compound having a ceramic raw material, a binder and a spherical or granular combustible material having adhesiveness to the binder. The green compact is fired to form the ceramic sintered compact including the electrode and containing about 35 to 80 volume percent pores. The pores of the ceramic sintered compact are filled with resin or glass.

Ceramic electronic component and method for making the same

A method of producing a bead inductor includes the steps of forming an outer portion outside of a conductor coil, and forming a molded body with the conductor coil embedded therein. The outer portion is formed outside of the conductor coil by disposing the conductor coil in a cavity defined by first and second mold portions, with first and second gates formed in the first mold portion, inserting first and second spacer pin portions, which define a spacer pin which passes through the conductor coil and extends to and closes the second gate, and supplying material containing magnetic powder into the mold cavity from the first gate. The molded body is formed by closing the first gate after the formation of the outer portion, and supplying from the second gate material containing magnetic powder into a space formed by removing the spacer pin portions.

Apparatus for manufacturing bead inductor

A radiation noise inhibiting component includes a magnetic sheet having a conductor layer which is bonded to the upper side of a CPU mounted on a circuit board. The conductor layer is provided on the surface of the magnetic sheet. The magnetic sheet lies between the conductor layer and the CPU. The conductor layer is grounded to the ground pattern on the circuit board through a conductor.

Radiation noise suppressing component attachment structure

A bead inductor includes a conductor coil defined by a wound, coated metallic wire, and an insulation coating which is removed on both end portions thereof. The conductor coil is embedded in a molded body with the end portions of the conductor coil being exposed at both end portions of the molded body. External terminals are attached to end portions of the conductor coil at both ends of the molded body so that the external terminals are electrically connected to the end portions of the conductor coil.

Bead inductor

A bead inductor with reliable electrical characteristics and which is constructed so as to be easily mass produced includes a substantially rectangular-parallelepiped core. The core includes an axial portion and an outer peripheral portion, and a coil is formed by winding a metal wire around the axial portion. The axial portion includes a central portion and a peripheral portion. A high strength material is used for the central portion. Metal caps are disposed on both ends of the core. The caps and the coil are connected electrically. In addition, the central portion of the axial portion may be a cavity.

An LC filter includes a capacitor with a small residual inductance, and having a good attenuation property up to a high frequency range, so as to achieve a strong attenuation at particular frequencies and also being adapted for use with a large current. Two coils including a metal plate arranged in a spiral shape, are disposed in a serially connected state so as to generate a mutual inductance therebetween. Also, a capacitor electrode plate has a shape which is included in the shape of the coils when viewed from the axial direction thereof, in the vicinity of the connection point of the coils so as to be opposed to a portion of the coils, whereby the portion of the coils functions as a capacitor electrode.

LC filter with capacitor electrode plate not interfering with flux of two coils

Method of manufacturing bead inductor

A radiant noise inhibiting assembly is constructed to inhibit a radiant noise in an electric cable connected to a digital type electronic device. The electric cable is covered by a substantially cylindrical magnetic structure which is constructed to act as a magnetic shield. A substantially cylindrical electrically conductive structure functioning as an electrostatic shield is disposed on the outside of the magnetic structure. Only a first end of the electrically conductive structure is connected to a ground of the electronic device, which first end is closer to the electronic device than a second end of the electrically conductive structure, which is not grounded. In this way, a portion of the radiant noise which is not completely absorbed by the substantially cylindrical magnetic structure is absorbed by the substantially cylindrical electrically conductive structure, thereby sufficiently inhibiting the radiant noise of the electric cable. Further, a substantially cylindrical case which is constructed to function as an electrically conductive structure and provide a function of an electrostatic shield is used. Thus, attaching such a substantially cylindrical case is the same as attaching an electrically conductive structure.

Radiant noise inhibiting assembly

A noise-suppressing component includes a ring-shaped ceramic core and an insulating member with which the surface of the ring-shaped ceramic core is coated having magnetic powder. Ceramic ferrite having an initial magnetic permeability of approximately 50 to 1500, for example, is used for the ring-shaped ceramic core. Resin including magnetic powder having an initial magnetic permeability of approximately 2 to 50 or rubber including the magnetic powder, for example, is used for the insulating member having the magnetic powder. The insulating member having the magnetic powder includes magnetic powder having an average particle diameter of approximately 1 to 1000 &mgr;m and has a magnetic-powder content of approximately 20 to 70 percent by volume.

Noise-suppressing component

A method of manufacturing a bead inductor prevents deformation of a metal coil or dislocation of the axis position of the metal coil caused by injection pressure at the time of injecting a molten resin material from a gate. A coil is fitted onto a coil supporting pin provided on a first lower mold used for injection molding in a cavity of the mold such that the inner periphery of the coil is in close contact with the coil supporting pin. A molten, resin material is injected into the cavity. Then, the coil supporting pin and the first lower mold are removed from the molded product, and a second lower mold without a coil supporting pin is provided for replacing the first lower mold. A molten resin material is injected into the space which had been occupied by the coil supporting pin. After removing the hardened resin molded product from the mold for injection molding, the end parts of the coil are cut so as to be exposed.

Method of manufacturing inductor

An inductor includes a coiled metal wire, an insulating molded member in which the coiled metal wire is embedded, and metal caps fitted on both ends of the insulating molded member. The metal caps are welded to both ends of the coiled metal wire. Between the metal caps and the end surfaces of the insulating molded member, spaces are defined respectively. The insulating molded member is made of, for example, resin or rubber.

Inductor and method of manufacturing same

A noise suppressing apparatus includes a magnetic body including a ferrite, a coiled conductor extending through the magnetic body, a pair of external electrodes provided on the surface of the magnetic body so that an electric current flows through the coiled conductor therebetween and a ground electrode covering at least a main portion of the magnetic body between the external electrodes on the surface of the magnetic body.

Growing community of inventors

Omihachiman, Japan

Masami Sugitani